about 220 degrees driving down the highway.new radiator,timing set properly,160 t-stat.what should this car be running?

170

I run around 220 on the highway

220 seems high to me, but that is just me. I have a 160 stat in mine and I was running at 170-180. I now have everything torn down and engine will be getting a rebuild, so we shall see what it will be after that.

Also depends on outside temperature, ......in Texas in Augusts I was running 200-205 after several fixes...when I bought it it was running 230-235, (straight aways 230 ,ea uphill it would climb to 235 and I was praying for lat ground)...but in non summer times, around 180 (after the fixes)
You say its a 400 do you have the 'fillers"...the masticated (now rubber) ones on either side of the bottom of the radiator? Those accounted for 5-10 F on mine (mine were missing at purchase)...also, do you have the bottom metal filler? (I did when I bought mine) and lastly is it an AC car? all 400s and AC cars had those fillers .
PO had also installed a pusher helper fan that I removed , it was blocking more air than it helped.
what about the water pump?
https://firstgenfirebird.org/forums/ubbthreads.php?ubb=showflat&Number=107803&gonew=1#UNREAD

radiator is a new one.three core.water pump is getting replaced.i took it off for inspection.i didnt see anything obvious wrong.car is non a.c.it is missing the lower panel and im unsure what the pieces are under the radiator.

thanks aaron

While all the fillers and baffles are good factory tweaks, I should point out my 455 runs all summer long at the temp of my thermostat (185) without the factory filler panels, lower baffle or rubber fillers installed (stripped down for paint eventually)

Did you tweak the divider plate on the water pump for a close tolerance like Bjorn suggests? A lot of people have found that makes a HUGE difference.

I am also running the biggest FB aluminum radiator that Rodney Red makes

My car runs at 180. The only time I have seen it creep up a little is sitting in traffic with the air conditioning on. And then it only got to 200. Having the correct fitment of a 7 blade fan into the shroud is key.

And the rubber pieces are not under the radiator, they close off the holes on either side of radiator at bottom....one of the rubber(masticated) fillers was missing on mine...added a new in , it changed 5 F........if you have neither, add them in...think they are $14 /set at Ames ,or at least were....tweak the water pump. these are easy/cheap fixes , always go for the cheaper fixes first....I had a three core aluminum (Champion) radiator on mine (did it the last 3 years I had the car)...it brought my temps down the last 10F to 185 in summer...I gradually got mine to go down from 230 to 220 to 205 to 195 , to 185 by doing these different items

also, even though radiator is ok, maybe need to flush the engine?

Is there a resource that shows all the stuff I'm supposed to have around the radiator?

I too am battling the temp issue.

6A-3 in the service manual for your 67. http://thefirstgensite.com/library/67fbservice/FI67S6A.pdf

I had the same issue with high temps in the 230 to 250 range, I tweeked the timing a little back and did what Bjorn has suggested with the water pumpo back plates, I got my space down as close to the impellers as I could without hitting and it now runs at 190 to 200 with a 180 thermostat even on days that it is in the 90's out. It does work.

If you have a clutch fan, you might check to see if the clutch is engaging when hot. Mine was bad, and replacing it made a huge difference.